From owner-freebsd-current Wed Jul 25 13:18:40 2001 Delivered-To: freebsd-current@freebsd.org Received: from mail12.speakeasy.net (mail12.speakeasy.net [216.254.0.212]) by hub.freebsd.org (Postfix) with SMTP id 4E82637B405 for ; Wed, 25 Jul 2001 13:18:37 -0700 (PDT) (envelope-from jhb@FreeBSD.org) Received: (qmail 92268 invoked from network); 25 Jul 2001 20:18:36 -0000 Received: from unknown (HELO laptop.baldwin.cx) ([64.81.54.73]) (envelope-sender ) by mail12.speakeasy.net (qmail-ldap-1.03) with SMTP for ; 25 Jul 2001 20:18:36 -0000 Message-ID: X-Mailer: XFMail 1.4.0 on FreeBSD X-Priority: 3 (Normal) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8bit MIME-Version: 1.0 In-Reply-To: <200107241207.VAA14339@zodiac.mech.utsunomiya-u.ac.jp> Date: Wed, 25 Jul 2001 13:18:35 -0700 (PDT) From: John Baldwin To: Kazutaka YOKOTA Subject: RE: Death sentence to KLD screen savers? Comments? Cc: freebsd-current@freebsd.org Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On 24-Jul-01 Kazutaka YOKOTA wrote: > This is to propose to abolish KLD screen saver modules. > > KLD screen savers have the following problems/deficiencies. > > - It is too easy to abuse the power of being run in the kernel > mode. The screen saver is invoked periodically once the console > becomes idle. It should not spend long time to draw something > to the screen. But, we may be tempted to do a bit more elaborate > drawing so that we get "interesting" effects. It's too easy to > degrade the system performance by staying in the screen saver > too long. You can stick the screen saver in a low priority kthread and achieve the same effect. > - While it is easy to manipulate the video board in the KLD module > (because we can go anywhere and access anything :-), there are > limitations. If you want to perform file I/O (to obtain some > bitmaps from files), or want to read some sort of configuration > file, there is no straight forward way to do so. You can use kldload or the loader with the -t 'foo' stuff to load configuration files, etc. that modules can get at. Just pointing out that userland is not the only way of achieving your goals. -- John Baldwin -- http://www.FreeBSD.org/~jhb/ PGP Key: http://www.baldwin.cx/~john/pgpkey.asc "Power Users Use the Power to Serve!" - http://www.FreeBSD.org/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message